1. Field of the Invention
This invention relates to an automatic washing machine agitator construction and more specifically to an agitator construction wherein the agitator is comprised of an oscillatory rotating lower portion and a vertically reciprocating and an oscillatory rotating upper portion.
2. Description of the Prior Art
A number of different types of agitating structures are disclosed in the prior art for automatic washing machines which provide both reciprocatory and rotary movement of an agitator. For example, U.S. Pat. Nos. 3,678,714, 4,452,054 and 4,520,638 all disclose upper agitator portions which are driven in a reciprocating vertical motion by the oscillatory motion of the agitator shaft.
U.S. Pat. No. 4,520,638 discloses an agitator thruster for an automatic washer for increasing the rollover of clothes during the agitation portion of a washing cycle wherein the thruster moves in a vertical reciprocating motion by action of a pin carried by the thruster engaging angled side walls of a channel in the agitator barrel and being caused to move in one direction around the channel circuit, up along one angled channel wall and down along another.
U.S. Pat. No. 4,452,054 discloses an agitator thruster for an automatic washer for increasing the rollover of clothes during the agitation portion of a washing cycle wherein the thruster moves in a vertical reciprocating motion by using inner and outer reversely spiraled cam surfaces and a driving barrel having a driving pin which alternately transfers to the inner and outer cam surfaces.
U.S. Pat. No. 3,678,714 discloses a washing machine assembly of the vertical axis type, including an agitator assembly which oscillates about a stationary vertical axis, in combination with a second agitator which is coupled to the main agitator for oscillation therewith, together with means operating between the main agitator and the other agitator to effect a vertical reciprocation of the latter during oscillation.